patch 8.2.2030: some tests fail on Mac

Problem:    Some tests fail on Mac.
Solution:   Avoid Mac test failures.  Add additional test for wildmenu.
            (Yegappan Lakshmanan, closes #7341)

src/testdir/runtest.vim

@@ -136,6 +136,13 @@ else
   let s:t_normal = &t_me
 endif
 
+if has('mac')
+  " In MacOS, when starting a shell in a terminal, a bash deprecation warning
+  " message is displayed. This breaks the terminal test. Disable the warning
+  " message.
+  let $BASH_SILENCE_DEPRECATION_WARNING = 1
+endif
+
 " Prepare for calling test_garbagecollect_now().
 let v:testing = 1